ICONLOOP recently posted a very helpful explanation of Decentralized Identifiers (DID).

Unlike existing centralized ID verification methods that depend on third party institutions or service providers that end up in control of private data, DID relies on no central systems, giving individuals complete control over their own data.

This could make self-sovereign identity a reality.

In existing centralized ID systems, your ID, passwords and personal data are stored on the server of the centralized ID provider or service provider.

In a decentralized ID system using DID, that data is stored only on your mobile device, completely under your control.

DID has four characteristics, namely, it is:

  • Persistent
  • Resolvable
  • Cryptographically verifiable
  • Decentralized

The World Wide Web Consortium (W3C) is leading efforts to define DID Document Syntax and make it open source.

According to W3C’s standardized DID format, DID is a “simple text string consisting of three parts: 1) the did URI scheme identifier, 2) the identifier for the DID method, and 3) the DID method-specific identifier.”

Are those really things, you ask? Apparently so.

  • DID scheme: the string’s prefix — always “did” — which identifies the string as a DID.
  • DID method: defines how the specific DID method scheme is implemented, i.e., how DIDs and DID documents are created, resolved, updated, and deactivated.
  • DID Method-Specific Identifier: The identifier used within the specific DID method.

Now, DID services have four key elements.

  • Issuer: The entity that verifies identity and issues certificates at the request of the Owner. Issuers include government organs and verification technology companies.
  • Owner: The actual owner of the personal data, including national ID numbers and passport numbers.
  • Verifier: The entity that needs the private data to provide services, such as ecommerce sites, banks and payment proxies.
  • Blockchain: Decentralized ledgers or networks that manage the DID and record the verification details.

DID services separate the Issuer and the Verifier — or to put it another way, the entity that issues the ID and the entities that use the ID. Instead, the Owner of the ID uses his wallet to directly manage his ID data, making it a self-sovereign ID.

The Issuer issues the Owner a certified ID, which is stored only on the Owner’s device. When the Owner uses a service, he can selectively provide only the information he needs to.

Digital ID systems based on DID resolve issues that result from the current monopolization of the personal ID by third parties, including the leak of personal data, at a time when mutual trust is growing in importance. They also return to users sovereignty over their own web identity and data.

ICONLOOP’s MyID is composed of smart contracts that create and manage DIDs and verifiable credentials, a server for storing APIs and related data for ease of use, and a server for managing everything. This allows users to easily connect DID to existing services. They also provide SDKs for issuers, verifiers and building DID wallets.

Additionally, they also provide a Vault system for managing private keys and a PDS for managing VCs and other private data in cloud form.

ICONLOOP’s DID technology is already being deployed in the real world.

  • Zzeung: Based on MyID, Zzeung encrypts and saves your verified ID data on your mobile phone. When you need to submit your personal data, you can directly choose which pieces of data to submit. Zzeung allows you to verify your real name when opening up bank accounts or engaging in other financial services, check in using simple QR codes, manage your certificates and more.
  • Nayana and Gangwon Health Up: These two platforms from the provincial government of Gangwon Province also use MyID. Nayana is an integrated service platform that simplifies administrative services, while Gangwon Health Up is a provincial healthcare platform for managing chronic diseases.
  • POSCO’s CHANGeUP GROUND: Korean steel giant POSCO’s startup incubator in Pohang uses DID to verify ID for entry control, logging guests, parking, reserving meeting rooms and the like.

While not mentioned in ICONLOOP’s post, MyID has also been put to work by two of South Korea’s biggest banks, Shinhan Bank and NH Bank.